1. Field of the Invention
The present invention relates to an imaging apparatus, a light emitting apparatus, and a camera system in which the imaging apparatus and the light emitting apparatus perform wireless communication using radio waves.
2. Description of the Related Art
In recent years, a camera system has been developed that wirelessly connects an imaging apparatus and a light emitting apparatus using radio waves. In this camera system, the imaging apparatus transmits a command to start a light emission to the light emitting apparatus using radio waves, and the light emitting apparatus receives the command to start a light emission.
However, in the above-described system, it may be difficult to synchronize an operation of the imaging apparatus and a light emission of the wirelessly connected light emitting apparatus depending on a usage environment due to an influence of, for example, an obstacle or an interference by another radio wave.
Therefore, Japanese Patent Application Laid-Open No. 2008-102337 discusses a method for inserting timing data in a packet to be transmitted from a master unit in a wireless light supplementation system, and changing a state of packet transmission at timing of start of the processing related to photography, thereby instructing a remote flash unit to start a light emission.
In the above-described system, a delay time appears, which includes, for example, a period of modulation and demodulation between digital signals and radio waves. However, the method discussed in Japanese Patent Application Laid-Open No. 2008-102337 is not configured in consideration of, for example, a modulation period at the radio wave transmission side, a demodulation period at the radio wave reception side, and a period of radio wave transfer from the transmission side to the reception side. Therefore, it is impossible to accurately synchronize an operation of the camera and a light emission of the remote flash unit.